1. Field of the Invention
The invention relates in general to an optical projection system capable of detecting projection image deformation, and more particularly to an optical projection system capable of determining whether a projection image is deformed through detecting a voltage signal of a reflected laser and an associated detection method.
2. Description of the Related Art
Current projectors may be applied in various circumstances, such as being fixed to a location in a conference room or a room of other uses, or as being placed removably on a table. Regardless of the application circumstances, current projectors require a manual manipulation for adjusting a status of a projection image.
A projection image suitable for viewing is a rectangle, and so projectors are commonly designed to project rectangular projection images. However, deformation of a projection image is often caused in the event of a relative tilt angle between the projector and a projection plane. A user is required to manually adjust the shape of the projection image at this point in order to restore the projection image to a rectangle or to mitigate the deformation of the projection image. Such correction is generally referred to as “keystone correction”.
Along with progresses in technologies, a volume of projectors is constantly miniaturized such that a projector may be apt as a component in a portable device, e.g., a portable handset, a camera, a video camera or a laptop computer. When such miniaturized projector is employed in the above portable devices, a relative tilt becomes more even liable between the miniaturized projector and a projection plane. Thus, complications and an impracticability issue may arise if the keystone correction is still to be performed manually.